A spectroscopic study of the vaterite form YBO3:Eu3+processed by sol–gel technique

In the vaterite form YBO3, Y3+ ions lie in three different polyhedra. The use of Eu3+ as fluorescent structural probe confirms such description by exhibiting three characteristic optical spectra which can be easily isolated using laser-induced site selective excitation. The 5D0-relaxation rate has been evaluated in the temperature range 300–15 K for YBO3:Eu (50 mol%) and EuBO3 samples. The recorded evolutions are explained by phonon-assisted energy transfer mechanism leading to cross-over from fast migration to limited diffusion process below 90 K.